Question

Two solid blocks of similar size are submerged in water. One block is of lead and the other is made of aluminium. On which of these blocks will the buoyant force be greater?
A. lead block
B. aluminium block
C. same on both the block
D. depends on the orientation of the blocks.

Answer 1

Hint: Buoyancy is defined as the force that makes the objects float. It is basically the force acting on a body which is partially or completely immersed in a fluid. Buoyancy is as a result of the differences in pressure experienced on opposite sides of a body immersed in a static fluid. It can also be called a buoyant force. Buoyancy is basically the phenomena because of the Buoyant Force.

Complete step by step answer:
When a body is kept inside a liquid it is having an upward force called a Buoyant Force. The phenomenon is known as buoyancy. It is an upward thrust given by a fluid which will be equally opposite to the weight of an object placed in a fluid. As we all know, the lead is denser than aluminium. For an equal mass, volume will be inversely proportional to its density. Therefore the aluminium will be greater than the lead. As the volume is greater for the aluminium, the buoyant force experienced on it in water will be higher than that of lead.

So, the correct answer is “Option B”.

Note: As we all know, the pressure in a fluid column will increase with the depth inside the fluid. Therefore, the pressure at the lowest part of the body which is immersed in the fluid will be higher than that at the top. The difference in this pressure will cause a resultant upward force on the body which is defined as buoyancy.